1. Technical Field
The present invention relates to a liquid ejecting head which ejects liquid from nozzle openings, a liquid ejecting apparatus which includes the liquid ejecting head, a piezoelectric element which is loaded on the liquid ejecting head, and a manufacturing method thereof.
2. Related Art
There is known a liquid ejecting head which ejects liquid droplets from nozzle openings communicating with a pressure generation chamber, by deforming a piezoelectric element (piezoelectric actuator) to generate pressure fluctuation in the liquid in the pressure generation chamber. As a representative example of this liquid ejecting head, there is an ink jet type recording head which ejects ink droplets as the liquid droplets.
The ink jet type recording head, for example, includes a piezoelectric element on one surface side of a flow path formation substrate on which a pressure generation chamber communicating with nozzle openings is provided, and ejects ink droplets from the nozzle openings by generating a pressure change in ink in the pressure generation chamber by deforming a vibrating plate with driving of the piezoelectric element.
Herein, the piezoelectric element includes a first electrode, a piezoelectric layer, and a second electrode provided on the vibrating plate, and a wiring layer for connecting with a wire connected to a driving IC or the like is connected to the first electrode and the second electrode (for example, see JP-A-2008-114370, JP-A-2009-172878, and JP-A-2009-196329).
However, if an adhesion layer is patterned by wet etching, using the adhesion layer such as nickel chrome as the wiring layer, since acid is used as an etchant which is used when performing the wet etching of the adhesion layer, electric corrosion may occur in the electrodes due to the acid, and peeling-off of the electrode or peeling-off of the wiring layer may occur.
In addition, if acid is used when performing the wet etching of the adhesion layer, this acid may damage the piezoelectric layer.
If gold or the like is used as a conductive layer to be formed on the adhesion layer, it costs a lot.
Such problems do not only occur in the ink jet type recording head, but also occur in a liquid ejecting head which ejects liquid other than ink, in the same manner. In addition, the problems are not limited to the piezoelectric element to be loaded on the liquid ejecting head, but they can occur in a piezoelectric element to be loaded on the other devices, in the same manner.